Ribbon corrugation, rounded or pointed?

What is the difference when corrugating a ribbon with rounded corrugation vs sharp sawtooth corrugation?

I notice that high end manufacturers don't seem to use sawtooth corrugation much, do they have more resonance due to the flat faces or something?

I would imagine that a sharper edges corrugation would be more difficult to deform into standing waves though.
I would imagine that a sharper edges corrugation would be more difficult to deform into standing waves though.[/QUOTE]

Given equal ribbon weight to either profile, a gut feeling says a more limp sharp edge might actually be prone to increased excitation of its mass than a more rigid
or gently curved ribbon design

Pure speculations on my part though

When a sharp bend occurs in aluminum you work harden that edge and now you are prone to a stress fracture along that edge.

If you never moved it again then all would be well , but that isn’t the environment
a ribbon will be working in. You will be stressing it even more and all around this stress point

Just another consideration
The force resulting from the interaction of the current with the magnetic field is always perpendicular to the current flow. If the ribbon has a perfect triangle corrugation the force will be 45 degrees off in either direction depending on the side of the triangle. This was my reasoning for choosing a sinusoidal corrugation.


2016-01-26 12:46 am
haven't measured distortion BUT have made varieties of V shaped and rounded corrugations in pitches ranging from approximation 1.5 to 3 mm

I was looking primarily at the resonance that happens roughly between 3 and 10khz depending on corrugation size/ribbon width/ and diaphragm material.

If the pitch/ size of the two corrugation types were the same , the resonances and waterfall looked about the same and the overall freq response was close as well

I didn't see any useful difference between them

I did not do destructive testing on the V shaped ones to see if they failed any sooner than the rounded variety so dont really know about their durability